title: Feasibility of temporary biventricular pacing after off-pump coronary artery bypass grafting in patients with reduced left ventricular function.
abstract: In selected patients undergoing cardiac surgery, our research group previously showed that optimized temporary biventricular pacing can increase cardiac output one hour after weaning from cardiopulmonary bypass. Whether pacing is effective after beating-heart surgery is unknown. Accordingly, in this study we examined the feasibility of temporary biventricular pacing after off-pump coronary artery bypass grafting. The effects of optimized pacing on cardiac output were measured with an electromagnetic aortic flow probe at the conclusion of surgery in 5 patients with a preoperative mean left ventricular ejection fraction of 0.26 (range, 0.15-0.35). Atrioventricular (7) and interventricular (9) delay settings were optimized in randomized order. Cardiac output with optimized biventricular pacing was 4.2 ± 0.7 L/min; in sinus rhythm, it was 3.8 ± 0.5 L/min. Atrial pacing at a matched heart rate resulted in cardiac output intermediate to that of sinus rhythm and biventricular pacing (4 ± 0.6 L/min). Optimization of atrioventricular and interventricular delay, in comparison with nominal settings, trended toward increased flow. This study shows that temporary biventricular pacing is feasible in patients with preoperative left ventricular dysfunction who are undergoing off-pump coronary artery bypass grafting. Further study of the possible clinical benefits of this intervention is warranted.
authors.affiliation: Departments of Medicine (Dr. Wang), Surgery (Drs. Naka, Smith, H. Spotnitz, M. Spotnitz, and Stewart, and Mr. Cabreriza and Ms Kelly), Pediatrics (Dr. Richmond), and Biostatistics (Dr. Cheng), Columbia University, New York, NY 10032; and National Heart and Lung Institute (Dr. Quinn), Imperial College London, Harefield Heart Science Centre, Harefield UB9 6JH, United Kingdom.
authors.forename: Daniel Y
authors.initials: DY
authors.lastname: Wang
authors.forename: Lauren A
authors.initials: LA
authors.lastname: Kelly
authors.forename: Marc E
authors.initials: ME
authors.lastname: Richmond
authors.forename: T Alexander
authors.initials: TA
authors.lastname: Quinn
authors.forename: Bin
authors.initials: B
authors.lastname: Cheng
authors.forename: Michelle D
authors.initials: MD
authors.lastname: Spotnitz
authors.forename: Santos E
authors.initials: SE
authors.lastname: Cabreriza
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Naka
authors.forename: Allan S
authors.initials: AS
authors.lastname: Stewart
authors.forename: Craig R
authors.initials: CR
authors.lastname: Smith
authors.forename: Henry M
authors.initials: HM
authors.lastname: Spotnitz
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods; D047549:Coronary Artery Bypass, Off-Pump / Q000009:adverse effects*; D003324:Coronary Artery Disease / Q000175:diagnosis / Q000503:physiopathology / Q000601:surgery*; D004562:Electrocardiography; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D013997:Time Factors; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D016277:Ventricular Function, Left
keywords: Arrhythmias, cardiac/therapy; cardiac output, low/therapy; cardiac pacing, artificial/methods; heart failure/therapy; stroke volume; ventricular dysfunction, left/complications/prevention & control